Putting is an important part of golfing. Accurate putting requires attention to speed/distance and line. Speed/distance is controlled by the velocity and force applied to a ball, while line defines the direction of the moving ball. The line can only be made by the golfer, but the speed can be aided by a more consistent roll. A top spin roll is generally most desired because it is less likely to be affected by bumps on the green which might otherwise effect the line of the ball. Many golf putter designs have attempted to aid the golfer in producing a moving ball that has an appropriate top spin roll.
Another problem with accuracy in putting is caused by ground interaction. A golfer usually lines up the putter with the ball (“at address”), brings the club back (“takeaway”), and then hits the ball and follows through. The desired results are obtained when the putter is kept exactly as the golfer intended it. However, the putter is usually touching the ground at address. During takeaway, the putter may interact with the ground (“ground interaction”). The golfer aims to keep the putter slightly above the ground during the rest of the takeaway and follow through. However, sometimes the putter does touch the ground. Even the most carefully manicured course includes some irregularities in its greens. This can affect the aiming of the putter, and hence effect the line of the ball.
Another problem with accuracy in putting is caused by twisting of the putter during the stroke causing the striking face of the to strike the ball at an angle off of the line of ball resulting in an undesired ball trajectory.
Another problem with accuracy in putting is caused by an incorrect approach to the golf ball to be struck resulting in the ball being off center from the sweet spot or correct strike location on the striking surface.